The present invention relates to the technical field of solar power generation, in particular to a bi-facial photovoltaic power generation module.
Under the background of increasingly serious energy shortage and environmental pollution, the development of renewable energy has become a major global issue. Solar cells, also known as “solar chips” or “photocells”, are photoelectric semiconductor chips that generate electricity directly by making use of the sunlight. As long as such solar cell is illuminated under certain illumination conditions, it can output voltage in an instant and generate current in the case of a circuit. Therefore, the use of solar energy is an important direction for developing renewable energy sources. However, the higher production cost restricts its application scope. With the drastic reduction of government subsidies, it is an urgent problem for all manufacturers to reduce the production cost of cells and improve the power generation efficiency.
With the development of photovoltaic market, people's demand for high-efficiency crystalline silicon solar cells is becoming more and more urgent. More than 85% of the commercial solar cell market is still occupied by crystalline silicon solar cell products, and the cost-performance competition around efficiency and cost is very fierce. Monocrystalline silicon solar cells are mainly made of P-type and N-type substrates. Due to the cost advantages in substrate price and non-silicon cost, the current main market products are still P-type monocrystalline silicon solar cells. Compared with P-type crystalline silicon cells, N-type crystalline silicon has a large diffusion length in its minority carriers because it is insensitive to metal impurities or has good endurance. In addition, the N-type crystalline silicon is doped with phosphorus without formation of cell string-O complex due to illumination, so there is no light-induced deterioration in the P-type crystalline silicon cell. Therefore, the N-type crystalline silicon cells have gradually become the focus of many research institutions and photovoltaic enterprises.
Meanwhile, with the increasing global installed capacity of solar energy, there is less and less photovoltaic land available. In the market, it is more and more urgent to improve the power generation efficiency of photovoltaic modules, reduce the cost per kilowatt hour of the electricity generated by the photovoltaic modules, and improve the return on investment of photovoltaic system power stations. At present, all photovoltaic modules generate electricity through cells at front sides thereof, the power of a single cell is only 3 watts, and the power generation efficiency is relatively low.